import com.sun.source.tree.Tree;

import java.util.LinkedList;
import java.util.Queue;

class TreeNode {
    int val;
    TreeNode leftNode;
    TreeNode rightNode;

    public TreeNode(int val) {
        this.val = val;
    }
}

public class Test1 {
    public static void main(String[] args) {
        Queue<TreeNode> queue = new LinkedList<>();

        TreeNode node1 = new TreeNode(1);
        TreeNode node2 = new TreeNode(1);
        TreeNode node3 = new TreeNode(1);

//        queue.offer(null);
//        queue.offer(null);
//        queue.offer(null);
//        queue.offer(null);

        queue.offer(node1);
        queue.offer(node2);
        queue.offer(node3);
        queue.offer(null);
        queue.offer(null);

        System.out.println(queue.size());
    }
}
